"In the examined adult population the first illicit drug use took place most frequently at the age of 17 and at the age of 18 and a half on average. More than a half (55%) of ever users tried illicit drugs at the age of 18 or younger, every sixth-seventh user (15.3%) had already used drugs at the age of 15 and every fourth user at the age of 16.
"The cumulated prevalence curve calculated on the basis of age of first drug use shows that in the 19-64 year old adult population the proportion of people trying illicit drugs rose practically evenly between the ages of 14 and 20, i.e. in every age year a further half-one percent of the population came into contact with drugs. In the following years the risk of coming into contact with drugs is minimised, and practically ceases to exist after the age of 28. Beside the more intensive risks in specific age, the exposure period for today’s young adults is similar to that of the adult population: intensive between 14 and 20 years, 1-3% in the individual age years, then there is a reducing risk and after the age of 25 first use can no longer be experienced."

Source

Drog Fókuszpont, "2014 National Report (2013 Data) to the EMCDDA by the Reitox National Focal Point - Hungary: New Development, Trends" (Budapest, Hungary: Drog Focuszpont 2014), pp. 19-20.
http://www.emcdda.europa.eu/p…
http://www.emcdda.europa.eu/a…